diff --git a/cuda_bindings/setup.py b/cuda_bindings/setup.py
index 0bddead973..b2e39a10b8 100644
--- a/cuda_bindings/setup.py
+++ b/cuda_bindings/setup.py
@@ -329,7 +329,7 @@ def do_cythonize(extensions):
     return cythonize(
         extensions,
         nthreads=nthreads,
-        compiler_directives=dict(language_level=3, embedsignature=True, binding=True),
+        compiler_directives=dict(language_level=3, embedsignature=True, binding=True, freethreading_compatible=True),
         **extra_cythonize_kwargs,
     )
 
diff --git a/cuda_bindings/tests/cython/build_tests.bat b/cuda_bindings/tests/cython/build_tests.bat
index c56efac47f..fda860506e 100644
--- a/cuda_bindings/tests/cython/build_tests.bat
+++ b/cuda_bindings/tests/cython/build_tests.bat
@@ -5,5 +5,5 @@ REM SPDX-License-Identifier: LicenseRef-NVIDIA-SOFTWARE-LICENSE
 
 setlocal
 	set CL=%CL% /I"%CUDA_HOME%\include"
-	cythonize -3 -i %~dp0test_*.pyx
+	cythonize -3 -i -Xfreethreading_compatible=True %~dp0test_*.pyx
 endlocal
diff --git a/cuda_bindings/tests/cython/build_tests.sh b/cuda_bindings/tests/cython/build_tests.sh
index 50a16b6930..1e08f35955 100755
--- a/cuda_bindings/tests/cython/build_tests.sh
+++ b/cuda_bindings/tests/cython/build_tests.sh
@@ -14,4 +14,4 @@ else
   exit 1
 fi
 
-cythonize -3 -i ${SCRIPTPATH}/test_*.pyx
+cythonize -3 -i -Xfreethreading_compatible=True ${SCRIPTPATH}/test_*.pyx
diff --git a/cuda_core/build_hooks.py b/cuda_core/build_hooks.py
index ab54e4bca2..e38f5676df 100644
--- a/cuda_core/build_hooks.py
+++ b/cuda_core/build_hooks.py
@@ -101,7 +101,7 @@ def get_cuda_paths():
         verbose=True,
         language_level=3,
         nthreads=nthreads,
-        compiler_directives={"embedsignature": True, "warn.deprecated.IF": False},
+        compiler_directives={"embedsignature": True, "warn.deprecated.IF": False, "freethreading_compatible": True},
         compile_time_env=compile_time_env,
     )
 
diff --git a/cuda_core/pyproject.toml b/cuda_core/pyproject.toml
index 8bbfca07d6..5f12f6f120 100644
--- a/cuda_core/pyproject.toml
+++ b/cuda_core/pyproject.toml
@@ -51,7 +51,7 @@ cu12 = ["cuda-bindings[all]==12.*"]
 cu13 = ["cuda-bindings[all]==13.*"]
 
 [dependency-groups]
-test = ["cython>=3.0", "setuptools", "pytest>=6.2.4"]
+test = ["cython>=3.1", "setuptools", "pytest>=6.2.4"]
 test-cu12 = ["cuda-core[test]", "cupy-cuda12x; python_version < '3.14'", "cuda-toolkit[cudart]==12.*"]  # runtime headers needed by CuPy
 test-cu13 = ["cuda-core[test]", "cupy-cuda13x; python_version < '3.14'", "cuda-toolkit[cudart]==13.*"]  # runtime headers needed by CuPy
 # free threaded build, cupy doesn't support free-threaded builds yet, so avoid installing it for now
diff --git a/cuda_core/tests/cython/build_tests.sh b/cuda_core/tests/cython/build_tests.sh
index 1c36259c08..eb3303840d 100755
--- a/cuda_core/tests/cython/build_tests.sh
+++ b/cuda_core/tests/cython/build_tests.sh
@@ -15,4 +15,4 @@ else
   exit 1
 fi
 
-cythonize -3 -i ${SCRIPTPATH}/test_*.pyx
+cythonize -3 -i -Xfreethreading_compatible=True ${SCRIPTPATH}/test_*.pyx